Packages and packaging articles



United States Patent 2,724, 50 PACKAGES AND PACKAGING ARTICLES DanielMelnick, Teaneck, N. 1., assiguor to The Best Foods, Inc., New York, N.Y., a corporation of New Jersey No Drawing. Application July 18, 1952,

, Serial No. 299,761

11 Claims. (Cl. 99 179) The present invention relates to protectivepackaging and wrapping material and more particularly to protectivewrapping and cartoning material for protecting oleaginous foods whichare ordinarily solids at room temperatures from fungus and bacterialcontamination. The protective packaging materials of the invention aremost suitable for use as parchment wrappers and waxed cartonsforpackaging margarine and butter.

It is an object of the present invention to provide a protectivewrapping material which will prevent oleaginous food materials,anddesirably oleaginous-aqueous materials which are normally solids atroom temperature, such as the bread spreads: butter and margarine, frombecoming contaminated by molds under the most adverse conditions ofstorage. A

It is a further object of the present invention to provide a wrappingand cartoning material impregnated with a fungistatic composition whichis easily applied and will protect the contents from external funguscontamination.

It is an additional object of the present invention to provide afungistatic wrapping and cartoning material which will successfullyprotect the wrapped contents from external fungus contamination withoutdirect incorporation of a fungistatic agent into the packaged contentsthemselves. It is also an object to provide wrapping material which willnot impart more than infinitesimal and incidental amounts of fungistaticagent to the wrapped contents.

Mold contamination of bread spreads, including butter and margarine, isa serious problem facing the processing industry and the retaildistributor. When mold contamination of a bread spread is discovered,the consumer is justified in returning the product. This results in notonly a costly problem for the manufacturer but must inevitably result insome damage to his reputation. Quite frequently, entire batches ofproduct of the same code number are returned, even though the incidenceof mold spoilage in those batches wassmall. Upon the return of moldlyprints, it is not possible to segregate the moldy prints from theuncontaminated ones; for while it is possible to subject the individualprints to visual examination, the unaffected prints may not be salvagedsince the product must be stripped of its wrapping as part of theexamination. Even if no visual signs of contamination are found, it isnot possible to re-wrap and package these prints since they have beenexposed to the air and may be subject to new contamination or they mayalready be infested with an early stage of mold growth which is notdetectable upon visual examination.

While bread spreads, such as butter and margarine, are processed underthe highest conditions of cleanliness by reputable manufacturers, theseproducts are not sterile. Regardless of how microbiologically clean thebutter or margarine may be as a result of manufacturing cleanliness, theproduct may still become contaminated after packaging. Under conditionsof variable, uncontrolled humidity and elevated temperatures, such asmay result in retail outlets, oil staining of the carton may occur.

This is due to the melted oils or fats in the bread spread leakingthrough the parchment wrapping and dissolving the parafiin coating ofthe carton itself. After the paraf fin coating has been dissolved in theoil exudate, the exposed cellulosic material of the carton becomes agood medium for the propagation of airborne molds settling upon it. Theinner wrapper also made of cellulosic materials is in itself a goodmedium for supporting mold growth, even in the absence of oil leakagefrom the product. These molds can work their way into the product,primarily through the overlap of the inner wrapper.

While mold contamination is not a particularly pressing matter whereproper storage facilities are available, bread spreads, such asmargarine and butter, are often subjected to abusive treatment duringretail distribution. In fact, it is only the most highly progressiveretail outlets which have suflicient refrigeration facilities to protectthe large quantities of butter and particularly margarine which passthrough their normal sales channels. It is not uncommon to find largequantities of material placed on open unrefrigerated shelves in retailoutlets. During the summer months, this material may be subjected totemperatures far in excess of the melting point of the lower-meltingconstituents of the oleaginous component. The resulting oiling o with orwithout accompanying weeping (moisture separation) makes the butter ormargarine highly susceptible to external contamination from molds.

Bread spreads, such as butter and margarine, are characterized by a highminimal fat content of about They also contain an aqueous phasecontaining non-fat, milk solids. Salt is very frequently added in anamount up to 3.5% of the total weight of the bread spread for flavorpurposes and particularly as a protective measure against mold andbacterial spoilage of the product. Be-

cause of the nutrient aqueous phase of these bread spreads, molds cangrow on these products. With a total salt content which usually rangesfrom 2.0 to 3.5%, which is equivalent to 13 to 23% of the aqueous phase,a partially effective means of inhibiting mold growth on butters andmargarine is provided. The use of salt, plus the observance of.satisfactory processing conditions and proper refrigeration of theproduct before and after packaging, should assure these products offreedom from visually detectable mold contamination. Nevertheless, dueto the faulty storage practices in a large number of retail outlets,mold contamination is quite frequent and consumer complaints of moldybutter and margarine are common. For the above reasons, theincorporation of salt in the product is not in itself a satisfactoryremedy to overcome this difficulty. Molds are salt-tolerant organismswhich grow rapidly on a medium provided a high humidity, adequate oxygensupply, and optimal tem-. perature are maintained.

The bread spread industry has undertaken numerous measures, other thanthe use of salt, in an attempt to overcome mold contamination of theproduct. It is quite common for the manufacturer to add sodium benzoateto margarine up to an amount of 0.10% by weight of the total product aspermitted by law. Butter is usually not so treated. This treatment isalmost completely ineffectural. First of all, sodium benzoate in amargarine has no significant fungistatic activity; it is only when thebenzoic acid is available as the free acid that any protective effectis. to be noted. In present day practice, margarine is made fromnon-cultured milk having a pH of the aqueous phase of approximately 6.5.The butter .manufacturers attempt to adjust the pH of the aqueous phaseas near to neutrality as possible (pH 6.7 to 7.2). At these high pHvalues, very little, if any, free benzoic acid is liberated from thesodium salt. Accordingly, although the practice of using sodium benzoateis Widespread, its effect is primarily psychological and its valuesubstantially nil.

One approach to the problem which has been reasonably successful, hasbeen wrapping of the prints of bread spread with an aluminum foilwrapper having a parchment backing. This wrapper containing an aluminumouter surface is substantially impermeable to air and thus the growth ofmolds on the inner parchment surface or on the product itself is madedifficult. However, oil staining of the carton may still occur, evenwith aluminum foil, due to oil leakage at the folds or by the funnelingof the oil through pinholes in the foil. Although reasonably successful,aluminum foil wrapping, because of its considerable cost, is not asatisfactory solution of the problem facing this highly competitiveindustry, and adds to the cost to the consumer of the product.

Cellophane overwrapping of the carton (with a parchment inner wrapping)has been attempted but this is I not only valueless but actuallyincreases the susceptibility of the product (or more properly thepackage) to mold spoilage. Not only will cellophane itself support moldgrowth but it also serves as a barrier to moisture transfer, therebyinsuring a high humidity within the package at all times. The use ofcellophane thus makes the product more susceptible to moldcontamination.

Attempts have been made to solve the problem of moldy butter andmargarine by treating the wrapping and packaging materials with afungistatic material. It has been recognized that mold growth initiatesprimarily on the surface of the butter or margarine print, where thereis an available oxygen supply, rather than in the body of these prints.In margarine containing 0.1% benzoic acid or sodium benzoate, verylittle of the fungistatic material is at the surface of the print whereprotection is required. That material within the body of the print iswasted for all practical purposes. Other investigators have treated theinner surface (that facing the margarine) of the wrapper with an aqueousor alcoholic solution of benzoic acid or sodium benzoate. Tests of theproducts wrapped with these wrappers show that no fungistatic activityhad been imparted to the wrapper and no protection was provided for theproduct. In the course of drying the wrappers, it appears that thebenzoic acid had completely volatilized and this was not appreciated bythe prior art investigators. Sodium benzoate will remain on the wrappersbut due to the high pH of present day margarine and butter, thismaterial will not liberate free benzoic acid and thus providesnomeasurable fungistatic activity.

It is apparent that the prior art was concerned with placing fungistaticmaterial in direct contact with the surface of the print. Efforts weredirected entirely toward placing as much of the fungistatic agent aspossible in contact with the surface of the product.

The present invention comprises a cellulosic material suitable for useas a packaging material coated with a wax of a melting point of between125 and 165 F. wherein the wax contains not more than 2% of an edible,fat soluble, steam-distillable, organic carboxylic acid.

The desirable packaging materials for use in the invention are in thenature of parchment wrappers (which may be wrapped around a print ofbutter or margarine) and wax coated, stiff, paper board which may beused as a cartoning material. While satisfactory results are obtainedwith a brittle wax of a melting point of 125 to 165 F., preferredresults are obtained with a wax having a melting point of 135 to 155 F.It appears that waxes providing optimum results are those having amelting point of approximately 140 to 150 F.

The preferred coating waxes are the refined paratfin waxes. This type ofmaterial, sometimes called block paraffin, is a purified mixture of highmelting, crystalline hydrocarbons derived from petroleum. Hydrogenatedvegetable or glyceridic oils have also been found successful and it isintended that the term waxes, as used t the mechanics of packaging thebread spreads.

he to :3. in this specification and claims, shall include'hydrogen atedvegetable oils. Where a hydrogenated vegetable oil is used, it ispreferred that the iodine number of the oil be a value of 3 or iess.Hydrogenated vegetable oils having an iodine value in this range showless flavor or odor deterioration on standing and are thus moredesirable from the esthetic standpoint. Oils having a higher iodinevalue, on the other hand, are no less satisfactory from the standpointof fungistatic protection of the packaging material. The socalledmicrocrystalline waxes derived from petroleum may also be used, but as adiluent for the paraflfin (macrocrystalline) waxes or of thehydrogenated vegetable oils. The microcrystalline waxes are solidhydrocarbon mixtures of a molecular weight averaging higher than theparaffin waxes and possess plastic and adhesive properties. Theseplastic properties are desirable to prevent cracking of the wax coatingat the folds of the packaging material. it is believed that themicrocrystalline waxes function as a plasticizer. Amounts of from 10 to20% of the total wax material may desirably be a microcrystalline wax.Blocking, the sticking of cartons or wrappers one to the other, resultsmore frequently when the microcrystalline waxes are used exclusively asthe coating material. It is contemplated that various other plasticizersmay be used to provide certain physical properties, such as lustrousfinish as provided by polyethylene, and still remain within the scope ofthe present invention. The melting point of the wax referred to above isthat of the wax including any plasticizer which may be incorporated.

It has been customary for the packaging industry to supply the foodprocessor unwaxed parchment and waxed cartons for packaging breadspreads, in the latter case, the parafiin wax has a melting point of 128to 130 F. These waxes with lower melting point are objectionable in thatlimpid oil separating from the butter or margarine produces excessiveoil staining of the packaging materials. Products in such oil soakedwrappers have little sales appeal and may be further penalized bysupporting mold growth. These lower melting parafiins also have agreater tendency for blocking. This blocking" or sticking of one Wrapperunit to its neighbor occurs particularly in the summer months and it mayinterfere with It has been discovered that the fungistatic acids of theinvention may be readily released from these low melting waxes toprotect the bread spread but the advantages so gained are outweighed bythe disadvantages described above. Waxes melting above 165 F. areundesirable since the release of the fungistatic acids of the inventionoccurs to a very limited degree, thus hindering their effectiveness.Furthermore, the higher melting waxes require the use of much highertemperatures in coating the wrapping materials which results inexcessive volatilization of the fungistatic acids during the coatingoperation. The final objection to higher melting parafiin waxes (above165 F.) is the greater tendency for such waxes to crack at the folds ofthe packaging material and to even flake off.

Waxes having a melting point of between and 155 F. provide preferredresults. These waxes are substantially free from the disadvantagesdiscussed above relative to those waxes melting below 125 or above 165F. Waxes melting between 135 and 155 F. are particularly valuable andcritical in providing a packaging composition which Will providepractical fungistatic protection to the package and, therefore, thebread spread contents. Where paraffin waxes are employed, the preferredmelting point range is between 135 and 165 F. If hydrogenated vegetableoils are used, the preferred melting point range is between 125 and 155F. Optimum results are obtained in all cases where the wax has a meltingpoint of between and F.

The fungistatic acid dissolved in the wax is an edible, fat soluble,steam-distillable, organic carboxylic acid.

Conterhplated as desirable acids for use in the invention are thosehavingunsaturation next to the carboxyl group in accordance with thefollowing formula:

R1 Rs tw) R1-.(, --C.OOH That portion of the moleculecontaining theunsaturation may be either an aliphatic or aromatic hydrocarbon group.Where more than one unsaturated group exists, such unsaturation shall bepart of a conjugated double bond system with the alpha-betaunsaturation. In the formula given above, R1 is hydrogen, when R2 and Rscombine to complete a single carbocyclicnucleus; R1 is carbon of analiphatic group when R2 and Rs are hydrogens. Examples of such acidsare: crotonic, isocrotonic, alpha-hexenoic, benzoic, sorbic andpara-hydroxybenzoic acids. Thepreferred acids according to the inventionare benzoic, para-hydroxybenzoic, sorbic and alphahexenoic acids.Benzoic and sorbic acids are the most suitable. r

The fungistatic acids are to be incorporated in the wax coating of theouter carton and/or the inner parchment wrapper in an amount of not morethan 2% by weight of the wax coating and preferably: between 0.5 and1.0% by weight. It is possible to dissolve some of the acids in themelted waxes in much higher concentrations, viz., 5% in the case ofbenzoic and sorbic acids. However, on cooling these wax solutions,crystals of the fungistatic acids are deposited on the wax surface. Awrapper containing readily detectable crystals in the wax coating isobjectionablein appearance. At a 1.0% con-. centration, no crystallinedeposits are to be noted. Since as much as 50%. of the fungistatic acidmay be volatilized during the coating of the packaging material with thewax, the preferred initial concentration of acid in the heated waxsolution is 1.0 to 2.0%. Another disadvam tage of excessively highconcentrations of fungistatic acid in the wax coatings is the medicinalodor imparted to the packaging material. Above 2.0% concentration, theodor becomes objectionable and may adversely condition a customer towardthe product. 1

Due to the volatility of the fungistatic acids which are incorporatedinto the waxes in the present invention, loss of as much as 50% of the,acids may occur during the coating operation. However, by observingprecautions and following the process of the invention for incorporatingthe waxes upon the packaging materials, this loss may be convenientlyreduced to about 25%. The waxes containing thefungistatic acids areprepared for coating by dissolving an amount of the acid up to 2% in thewax by stirring and heating in the wax. "It is advisable not to exceedthe melting point of the wax by more than about F. It is also advisablethat the temperature of the wax bath not exceed the melting point ofthewax by more than 10 F. during the coating operation. The

wax may be applied to the wrapping materials by either of two methods.The first of these is the so-called dry waxing procedure. a This methodis essentially impregnationof the absorbent paper stock with the waxcontaining the fungistatic acid so as to fill up the minute spacingsbetween the fibers of the paper with wax. In this process, only a smallportion of wax remains as a surface coating. The second process istheso-calledfwet waxing process. The wax is applied as a continuous filmwith a relativelysmall portion of the wax impregnating the paper stock.Either of these procedures are well known to the paper coating art andthe term wax coating, as used in this specification, is intended toinclude both procedures for applying the wax to the packaging materials.If unnecessarily high temperatures are maintained during the coatingoperation, such as a temperature in excess of 175 F. or a temperaturemore than 10F. above the melting point of the wax, excessivevolatilization of the acid will result. For example, at a 212 F., all ofthe fungistatic acids to be used in accordance with the invention arelargely volatilized during the coating operation. Sorbic and hexenoicacids are more readily sublimed from the heated waxes while benzoic acidis more readily retained by the wax. When a temperature of 170 F. isused, a wax-holding period of no longer than four hours and preferablyone of less than two hours is employed, i. e., a maximal period of fourhours for the progressive addition to the trough of the same quantity ofwax at the start of the operation, keeping the wax in the coating troughat a constant level during this period. The treated packaging materialsnormally suffer no further loss in fungistatic acids under theircustomary conditions of storage. The cartons are usually stored instacks while the wrapping papers may be stored both in the form ofstacks or in rolls. If the packaging materials are exposed as individualcartons or wrappers and subjected to circulating air at F. for a periodof four weeks, an additional loss of 25% of the fungistatic acids issuffered. Such conditions represent the practical extreme in deleteriousconditions to which packaged butter or margarine may be exposed innormal distribution.

The essence of the present invention, which is novel to the packagingand food industry, is the protection of the packaging material fromfungus atack and only indirectly protection of the product itself.Butter and margarine may be processed under conditions of utmostcleanliness, so that the resulting product may be made microbiologicallyclean (although not sterile). These products will be so free of moldthat they will exhibit in accordance with prior art teachings, isexposed to abusive storage conditions (absence of refrigeration), theproduct and package becomes susceptible to mold contamination andgrowth. The resulting mold propagation may progress to such a degreethat even should the product be returned to proper conditions ofstorage, the mold growth will be so apparent that consumer rejection ofthe product will follow. As distinguished from the present invention,the prior art was directed to attempts to bring a fungistatic agent onthe wrapper surface into intimate contact with the surface of theproduct and/or to admix the fungistatic agent with the product itself.

As a result of the present invention, there is made available a dynamicprotection against mold contamination in the marketing of bread spreads.The fungistatic acid is held in reserve until conditions arise whereinthey are needed to combat fungus growth. Both margarine and butter aremade to melt in the range of to F. so that they will promptly dissolvein the mouth of the user and have desirable mouthing properties. Becausethe fat of these bread spreads is made up of a mixture of a large numberof difierent triglycen'des, these products will tend to exude the lowermelt.- ing oils when they reach 75 to 80 F. This separated oil fractionremains liquid at room temperature. A packaged bread spread is not injeopardy of becoming mold contaminated until these lower melting oilsare released from the product. It is normally only when these lowermelting oils seep through the Wrapping and reach the wax carton thatdanger exists. Theseparated oil is a solvent for the wax coating on thepackaging materials. Since elevated temperatures of storage arenecessary forthe melting of these oils, oil separation is apt to occuronly under poor conditions of storage. Also, under these conditions,optimal temperatures are provided for mold propagation on the packagingmaterials. It is under these unfavorable conditions of storage that thepackaging compositions of the present invention come into play. Sincethe wax coating contains fungistatic acids which dissolve in the oils,the fungistatic 75 agent is liberated from the wax by the separated oiland thereby creates a medium unfavorable for mold propagation. Thus, thefungistatic acids in the wax coatings are not released under properstorage temperatures (55 F. or less at which temperature mold growth isnil), and it is only when the acids are needed that they are releasedfrom the packaging coating.

Packaging materials in accordance with the present invention have beentested under various conditions of adverse storage and have been foundto be highly successful in'protecting the wrapped product from moldcontamination. The tests which will be described demonstrate the variousadvantageous properties of the packaging compositions of the presentinvention.

It is essential to the satisfactory performance of the treated packagingcompositions of the present invention that the reservoir of fungistaticacid shall not be unduly depleted during manufacture of the packagingmaterial or during satisfactory conditions of storage but will readilysupply adequate quantities of fungistatic acid at the time when oilseparation occurs from the butter or margarine due to adverse conditionsof storage. It is necessary that the acid used and the wax in which itis dissolved shall cooperate to function properly at the required timewith the oils separating from abused margarine or butter. It has beendiscovered that when the fungistatic acids described in accordance withthe present invention are dissolved in wax having a melting point withinthe range present invention, into the oil fraction which separates frommargarine at 80 F. Tests were conducted in accordance with the followingprocedure: Twenty gms. of'

parafiin wax or hydrogenated vegetable oil containing 1.0 per cent of afungistatic acid (sorbic) were melted and poured into a stainless steelpan of 22 cm. by 22 cm. After uniform distribution of the molten waxover the bottom surface, the pan was placed in a brine bath and chilledrapidly; this simulates the coating of wrapping ma terials. The hardenedwax was then scraped ofi yielding flakes 0.5 to 0.75 mm. thick. 1.25gms. of these flakes were placed in 100 ml. beakers and 48.75 gms. oflimpid oil separated from margarine at 80 F. were added. (This oil had amelting point of 82.8 F. and an iodine value of 75, whereas the originalmargarine oil had a melting point of 95 F. and an iodine value of 70.)These test systemswere held at 80 F; and the oil free of flakesperiodically analyzed for-sorbic acid content. The concentration of thisfungistatic acid determined spectrophotometrically (maximal absorptionat 255 millimicrons) was used as an index of wax dispersion or solution.The proper blank controls were included in the analyses. The experimentswere designed tosimulate the exposure of the wax coatings to the oildrippings from the bread spreads during abusive storage of the packagedproducts in retail outlets. The results are shown in Table I whichfollows:

TABLE I Solution of wax and fungistatic acid (sorbic acid) in the oilfraction separated from margarine at 80 F.

Solution of Wax and Sorbie M P of Acid in Oil at 80 F. aiter- Maiga'rmeMelting Iodine Fraction Wax P omt, Value 1 Day 4 Days 12 Days after12-day Percent of added wax and 2 2 sorbic acid dissolved 127 0 75 100100 83. 5 137 0 57 64 67 83. 8 154 0 27 5O 57 84. 6 Do 165 0 15 84. 6Hydrogenated peanut oil 120 44 51 71 71 84. 0 Hyidrogenated cottonseed139 1 6 0 3 8 48 63 8 4 Hydrogenated soybean oil. 152 1 10 35 42 86. 2Miergerystallinen 0 26 84 91 84. 8 0 0 18 35 48 84'. 7 Do 172 0 12 21 2684. 2

1 Melting point of margarine oil fraction was 828 F. prior tothe-addition of 48.75 parts of the oil to 1.25 parts of wax.

called for by the invention, they are not available to exhibitfungistasis according to conventional tests. For we ample, when 1% ofsorbic acid dissolved in a hot (140 F.) paraffin wax having a meltingpoint of 130 F. is coated upon the walls of a flask and cooled, exposureto water showed that none of the sorbic acid is extractable by thewater. This would appear to be disappointing since sorbic acid has evena greater distribution ratio (concentration of acid in the aqueous phaseto concentration of acid in the oil) than benzoic acid in the two phasesystem found in butter and in margarine. In conventional plating testsin which parafiin scales prepared from paraflin' solutions containing 1%benzoic acid or 1% sorbic acid were placed on wort agar plates and thesurface of the agar plates streaked with a mixed mold inoculum andincubated at 80 F. for a period of five days, no Zones of inhibitionaround the paraflin scales were noted, although no growth on the scalesthemselves was observed. The inoculum used in this test and elsewhere inthe specification is a mixture of the common molds isolated from saltedmargarine and butter returned from the trade because of mold spoilage.

Contrary to the findings by the conventional tests, it was discoveredthat sorbic acid will be released from the wax solutions, prescribed foruse in accordance with the r unsightly oil-stained very quickly.

scribed by the present invention, the' fungistatic acids are morereadily released but the waxes are then prone to cause blocking, thesticking of one carton or wrapper to its neighbor during packaging. Thepackaging materials coated with waxes of undesirably low melting pointsare too sensitive to attack from the separated oils, becoming Thehydrogenated vegetable oils are superior to the paraffin waxes ofcomparable melting point in that similar results may be obtained withhydrogenated vegetable oils of significantly lower melting point. Thattrue solution of the wax in the margarine oil fraction occurred isapparent from the increase in melting point of the oil on completion ofthe test(see last column of Table I). The failure to observe progressiveincrease in the melting point of the margarine oil fraction on exposureto the wax of progressive higher melting points is due to theprogressively lower degree of solubility of the wax of higher meltingpoint.

I The extent of t olatilization of the fungistatic acids 1 from theheated wax solutionsare illustrated in two tables for two of the.fungistatic acids are illustrative of the findings in the series.

TABLE II 10 to a higher degree. At 170 F., whichis'the ayerag'temperature of the wax in coating operations, aholding period of nolonger than four hours, and preferably of less than two hours, should beobserved, i. e., a maximal period of four hours for the progressiveaddition to the trough of the same quantity of wax at the start of theoperation, keeping the wax during this period at a constant level in thetrough. As an alternate or added safety measure the temperature of theheated wax should be maintained not at 170 F. but at about 10 F. abovethe melting point of the selected Wax. At the more moderate coatingtemperatures the hydrogenated vegetable oils are superiorto the paraffinwaxes in favoring benzoic acid retention. This is not noted atthe highVolatilization of benzoic acid from waxes held at elevated temperaturesHours at 140? F. Hours at 170 F. Hours at 212 F.

Wax 3" 2 4 a 24 2 4 o s 1 2 3 Percent loss of Benzoic Acid Paraffin 1278 16 63 21 67 76 95 11 38 69 Do. 137 4 10 58 29 44 69 8 35 68 154 6 9 143 14 31 31 t 49 70 16 28 50 165 5 7 1 2 1 13 i 59 83 14 65 Average 1 2 913 61 24 39 57 79 12 34 63 Hydrogenated peanut 011.. 120 0 0 13 13 3 1335 60 14 39 65 Hydrogenated cottonseed oil 139 1 4 5 24 2 11 24 50 14 2454 Hydrogenated soybean oil 152 7 11 15 2 24 15 20 34 61 I 8 30 Average-L. 1 2 9 19 7 15 31 57 12 31 53 1 In calculating the averages for allwaxes, the results at 140 F. onthe unmelted wax flakes were omitted.

. 3 Wax flakes not melted.

TABLE III Volatilization of sarbic acid from waxes held at elevatedtemperatures Hours at 140 F.

Hours at 170 F.

Hours at 212 F.

Wax 15" 2 s 24 Percent loss of Sorbic acid Average 1 Q. 7 22 25 66Hydrogenated peanut oil 120 a 10 10 14 40 Hydrogenated cottonseed oil..139 i 5 7 14 27 Hydrogenated soybean oil 152 0 0 8 z 8 Average 8 9 14 341 In calculating the averages for all waxes, the results at 140 F. onthe unmelted wax flakes were omitted.

1 Wax flakes not melted.

The above results are important in demonstrating that precautions mustbe exercised in preparing the fungistatic wrapping materials of thisinvention. The. wax in the troughs through which the carton board orparchment are passed in plant coating operations must not be excessivelyheated. At 212 F., all the fungistatic acids selected for inclusion inthe wax coatings are very volatile. Sorbic and hexenoic acids are morereadily temperature (212 F.) or in tests with the more volatilefungistatic acids.

Wrappers and cartons coated with a waxcontaining a fungistatic acid inaccordance with the present invention and produced on a commercial scaleof operations, were subjected to other tests to evaluate their efficacyin preventing mold contamination.

The following data indicated in Tables IV and V lost from the heatedWaxes, whilebenzoic acid is retained below shows the protection againstmold growth granted by the packaging compositions according to thepresent spread itself rather than on the outer surface of the invention:parchment. Measurable inhibition of mold growth was TABLE IV Fungistaticproperties of parchment wrappers before and after processing accordingto the present invention Mold Growth on Inocu- Parchment Example MeltingBenzoic W on latcd Wrappers l I Point Acid in m i I Gig/lax, Wax lief-Perlgnt Alt 3 Aft e v C811 9! 61 No. Description Weeks Weeks Regular,Unwaxed l l Waxed on both surfaces" 139 0 0 32 .do 150 0. 0 29 l Waxedon one surface. 139 0. 94 18 none Waxed on both suriaces. 139 O. 57 32none Waxed on one surface. 150 1.45 17 none Waxed on both surfaces 1500. 90 29 none 1 Parchment sheets were inoculated on both sides with amold-in-water suspension; the sheets were dried and then incubated at 80F. at 100% relative humidity. Relative mold growth is indicated bynumber of +s.

resistance to mold propagation. The presence of the 30 fungistatic acidrenders the wrapper remarkably resistant to molds. Given time, moldswill eventually grow on the wrapper coated with the fungistatic wax onone noted only in Examples 2 and 4, i. e., only in the case of themargarines in direct contact with the fungistatic wax. While coatingboth sides of the parchment may provide certain advantages in thisrespect, it is not an admirable practice in all respects; for not onlydoes it introduce some fungistatic acid into the product, but itsurface, but such growth is predominantly on the unwaxed surface. Thesusceptibility of the unwaxed surface to mold growth is of no practicalconcern since the objective of the present invention is the protectionof the microbiologically clean product through protection of the packagefrom contamination by adventitious molds during retail distribution andsale; the waxed coating would be on the parchment surface away from theproduct. for mold growth than parchment, when these wrappers themanufacture of the bread spread.

Tests were conducted on waxed cartons prepared according to the presentinvention. The cartons were waxed on both surfaces. Earlier tests haddemonstrated that the regular waxed carton is a far poorer medium TABLEV Fungistatic properties of parchment wrappers before and afterprocessing according to the present invention in protecting bread spreadand package 1 Parchment Example Mold Growth 1 After 3 weeks After 6weeks No. Description On gg On On 3.2 On Carton men; Product Carton mentProduct Regular, Unwaxed none Waxed on both Surfaces (wax=139 F., M. 1none Waxed on both surfaces (wax=150 F., M. P.) none Waxed on onesurface (wax=139 F., M. P.; 0.94% none none none i benzoic acid). Waxedon two surfaces (wax=139 F., M. P 0.57% none none none none none nonebenzoic acid). Waxed on one surface (wax=150 F., M. P.; 1A5% none nonenone i benzoic acid). Waxed on two surfaces (wax=l F., M. P.; 0.90% nonenone none none none none benzoic acid).

1 Illustrated with packaged margarine containing no fungistatic agentand stored at F. at relative humidity. Mold inoculum applied onparchment surface facing regular waxed carton; relative mold growth isindicated by the number of s.

The effectiveness of the present invention is well ilalone areinoculated and stored under conditions oplustrated by the above results.Tests were also contirnal for mold propagation. Accordingly, the cartonsducted with the mold inoculum applied to the bread 75 were tested beforeand after staining with margarine oil.

implicitly condones or permits insanitary practices in static acid,benzoic as such or as sodium benzoate, may be i i Y t 14 l I Typicalresults with benzoic acid as the fungistatic agent of acid in the wax,the quantity is exceedingly small, only in the Wax coating are shown inT able VI which follows:

Fungistatic properties of waxed cartons before and after processingaccording to the present invention 1 Cartons were inoculated on bothsides with a mold-ln-water suspension; the cartons were dried and thenfinleubated at 80 F. at 100% relative humidity. Relative mold growth isindicated by the numer s.

The above data are typical of observations made on products incommercial channels. Oil stainingof cartons is practicallyalways aprerequisite for molds to grow on The tgfg i g g fi ig gagigg for 1pound of the the cartons. Confirmatory results in tests conducted onbread spread gm 2:27 packaged margarine subjected to mold spoilage arepre- Weight wrapper of this inventim (1% sented in Table VII. Theprotective influence of the carpackaging materials are presented:

fungistatic acid in the wax coating of outer surface) gm 2.67

tons of this invention on the untreated parchment wrap- Weight t Weightof funglstatic acl agm 0.004 p r w al o pp r n l these tests- 3 Then,the concentration of fun c acid in r relation to product packed "percent 0.0009

TABLE VII Fungistatic properties of waxed cartons before and afterprocessing according toj the present invention in pro-- tecting breadspread and package 1 Carton Example Fungi- Mold Growth 1 After 6 weeksMelting static Wax Point of Acid on N D ri a i w gmoni 0 i P h 0- BS0 pOD. 3X 010611 ar on are i Percent ment Product Oontrol Regular. waxed130 0.0 15.2 5 Benzoic acid in w 137 1. 0 15. 6 none none -do 142 0.5715.5 none Sorbic acid in wax. 142 0. 14. 2 none illustrated withmargarine contaimn g no tungistatic agent wrapped in regular parchmentand stored at 80 F. at 100% relative humidity.

fit Told inoculum applied on both carton surfaces; relative mold growthis indicated by the number 0 s. l

Poolin both develo ments i. e. ache in the bread The ton:

g p p g g Weight of regular waxed carton for 1. pound of spread in boththe fungistatic wrappers and in the fungistatic cartons of thisinvention, imparted further resistance of the packaged product to moldspoilage. Under each circumstance no mold growth, despite deliberateinthe bread spread gm 21.50 Wax coating of both inner and outer surfacesc per cent" 15.0 Weight of wax coating gm 3.22 Weight of fungistaticacid (1% of the wax) oculations occurred on the acka in materials or onthe 0-032 bread spread after 6 to 8 w e eks gorige at 80 F. and. at$311533 i fifiiiifici idfi fifif ii cr ficff 0.007

100 per cent relative humidity. In these tests objectiontfg gg igg gfgfgg fungistatic acid in mm able oil staining of the packaging materialwas apparent tion to product packed per cent 0.008

When the parafiin waxes of melting point of less than 130 F. or thehydrogenated vegetable oils of fmelting point less than 125 F. were usedfor the coatings. Use of high melting coatings above 165 F., wasabandoned because of flaking difiiculties and interference with machineoperations due to the poor flexibility of the wrapping materials.

The preferable concentrations of fungistatic acid of 0.5

It is to be emphasized, however, that the objective of the presentinvention is not to furnish fungistatic acids to the bread spreads. Thepresent invention is intended to protect the packaging materials againstmold spoilage, the ordinary packaging materials having been shown tosupport mold growth as received or after having been in to 1.0 P cent inWax coating of the packaging contact with the bread spreadsduringabusive conditions terials for butter or margarine might beconsidered by of storage i analyses of margarmes and Butter frefi foodtechnologists to be a very high concentration, since 'f funglstauc afudsand stored at -80 for a in one of the two bread spreads (margarine) thefungi period of one month in the above wrappers have shown no detectableamounts (less than 0.00001%) of either added in a maximal concentrationof only 0.1 per cent. bellloic acid in the bread P Thatthe However, interms of absolute amount of fungistatic acid in Products Were abusedduring Storage was pp from relation .to product furnished by the higherconcentration 75 the oil stained condition of the wrapping materials.

one-twelfth of that ordinarily in the product. For purpose ofillustration, the results calculated for two typical Analyses of thesurfaces of the bread spreads, 1.0 mm. in depth, adjacentto. the oilstained areas of the package,

also have shown no detectable amounts of either fungistatic acid in theproducts; this latter analytical approach is a far more critical test ofthe possible migration of fungistatic acid into the product.

' The terms and expressions employed are used as terms of descriptionand not of limitation, and it is not intended, in the use of such termsand expressions, to exclude any equivalents of the features shown anddescribed or portions thereof, but recognize that various modificationsare possible within the scope of the invention claimed.

What is claimed is: V

1. A package comprising at least one print of a bread spread selectedfrom the class consisting of butter and margarine, said print beingprotected from fungus contamination by being wrapped in a cellulosicwrapper, said cellulosic material being susceptible to funguscontamination; said wrapper being coated on the exterior surface onlywith a Wax having a melting point of between 125 and 165 F. andcontaining therein not more than 2% of a fungistatic edible, fatsoluble, steam-distillable, organic carboxylic acid having unsaturationadjacent to the carboxyl group and that portion of the moleculecontaining the unsaturation is a member selected from the classconsisting of aliphatic and aromatic hydrocarbon groups and groupscontaining an additional unsaturated linkage making up a conjugateddouble bond system with the unsaturation adjacent to the carboxyl group.

2. A package comprising at least one print of a bread spread selectedfrom the class consisting of margarine and butter, said print beingprotected from fungus contamination by' being wrapped in a parchmentwrapper coated on the exterior side only with a wax and the wrappedbread spread packed in a carton of cellulosic board coated on both sideswith a wax; each of said waxes having a melting point of between 125 and165 F. and containing uniformly dispersed therein a fungistatic edible,fat soluble, steam-distillable, organic carboxylic acid havingunsaturation adjacent to the carboxyl group and that portion of themolecule containing the unsaturation is a member selected from the classconsisting of aliphatic and aromatic hydrocarbon groups and groupscontaining an additional unsaturated linkage making up a conjugateddouble bond system with the unsaturation adjacent to the carboxyl group.

3. An article comprising an oily exudable print selected.

from the group consisting of butter and margarine containing acellulosic wrapper thereabout which is susceptible to funguscontamination, said wrapper containing on the outer surface thereof onlya coating of wax having a melting point of between 125 and 165 F., andsaid wax coating being susceptible to the solubilizing eifects of anyexuded oil from said print and containing not more than about 2% ofa'fungistatic edible, fat soluble, steam-distillable, organic carboxylicacid having unsaturation adjacent to the carboxyl group and that portionof the molecule containing the unsaturation is a member selected fromthe class consisting of aliphatic and aromatic hydrocarbon groups andgroups containing an additional unsaturated linkage making up aconjugated double bond system'with the unsaturation adjacent to thecarboxyl group.

4. A packaging article for a bread spread selected from the classconsisting of margarine and butter comprising a cellulosic materialcoated with a wax of melting point of between 135 and 155 F. whichcontains therein not more than 2% of an edible, fat soluble,steam-distillable, organic carboxylic acid having unsaturation adjacentto the carboxyl group and that portion of the molecule containing theunsaturation is a member selected from the class consisting of aliphaticand aromatic hydrocarbon groups and groups containing an additionalunsaturated linkage'making up a conjugated double bond system with theunsaturation adjacent to the carboxyl group.

5. A packaging article for a bread spread selected from the classconsisting of margarine and butter comprising a cellulosic materialcoated with a wax of melting point of between 135 and 155 P. whichcontains therein not more than 2% of an edible, fat soluble,steam-distillable, organic carboxylic acid selected from the classconsisting of benzoic, pa rahydroxybenzoic, sorbic and hexenoic acids.

6. A cellulosic material susceptible to mold attack suitable for use asa parchment wrapper and a carton for packaging butter and margarine,said cellulosic material being coated with a wax of melting point ofbetween and 165 F. and containing therein not more than,2.0% of anorganic carboxylic acid selected from the class consisting of benzoic,parahydroxybenzoic, sorbic and hexenoic acids.

7. A. cellulosic material susceptible to mold attack suitable for use asa parchment wrapper and a carton for packaging butter and margarine,said cellulosic material being coated with a hydrogenated vegetable oilof melting point of between 125 and 155 F. and containing therein notmore than 2.0% of an organic carboxylic acid selected from the classconsisting of benzoic, parahydroxybenzoic, sorbic and hexenoic acids.

8. A parchment wrapper for wrapping butter and margarine, said parchmentbeing coated on one side only with a wax of melting point 125 to 165 F.,said wax containing therein not more than 2% of an edible, fat soluble,steam-distillable, organic carboxylic acid having unsaturation adjacentto the carboxyl group and that portion of the molecule containing theunsaturation is a member selected from the class consisting of aliphaticand aromatic hydrocarbon groups and groups containing an additionalunsaturated linkage making up a conjugated double bond system with theunsaturation adjacent to the carboxyl group, said coated side of saidparchment being intended to appear on the outer side of a wrappedpackage.

9. A parchment wrapper for wrapping butter and margarine, said parchmentbeing coated on one side only with a wax of melting point to B, said waxcontaining. therein 0.5 to 1.0% of a fat soluble, steam-distillableorganic carboxylic acid selected from the class consisting of benzoic,parahydroxybenzoic, sorbic and hexenoic acids; said coated side of saidparchment being intended to appear on the outer side of a wrappedpackage.

10. A cellulosic material susceptible to mold attack suitable for use asa wrapper for packaging a bread spread selected from the classconsisting of butter and margarine,

said cellulosic material being coated on one side only with ingunsaturation adjacent to the carboxyl group and that portion of themolecule containing the unsaturation is a member selected from the classconsisting of aliphatic and aromatic hydrocarbon groups and groupscontaining an additional unsaturated linkage making up a conjugateddouble bond system with the unsaturation adjacent to the carboxyl group.

ll. A cellulosic material susceptible to mold attack suitable for use asa wrapper for packaging a bread spread selected from the classconsisting of butter and margarine, said cellulosic material beingcoated on one side only with a coating which is intended to appear onthe outside when wrapped about the bread spread, said coating comprisinga wax having a melting point of between 135 and 155 F.

and containing therein between 0.5% and 1% of an acid selected from theclass consisting of benzoic, parahydroxybenzoic, sorbic and hexenoicacids.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS Mitchell Dec. 23, 1941 Ingie Aug. 4, 1942Abrams et a1. May 9, 1944 Gooding June 26, 1945 Coleman et a1. June 28,1949 Flett Aug. 23, 1949 Bennett Feb. 14, 1950 Coleman et a1 Sept. 4,1951 Cherepow et a1. Aug. 5, 1952 18 FOREIGN PATENTS 555,907 GreatBritain Sept. 13, 1943 110,841 Australia June 8, 1940 OTHER REFERENCESThe Journal Textile Institute, 1930, vol. 21, pages T245 to T259,article entitled The Inhibitory Action of Certain Substances on theGrowth of Mould Fungi, by R. G. Fargher et a1.

1. A PACKAGE COMPRISING AT LEAST ONE PRINT OF A BREAD SPREAD SELECTEDFROM THE CLASS CONSISTING OF BUTTER AND MARGARINE, SAID PRINT BEINGPROTECTED FROM FUNGUS CONTAMINATION BY BEING WRAPPED IN A CELLULOSICWRAPPER, SAID CELLULOSE MATERIAL BEING SUSCEPTIBLE TO FUNGUSCONTAMINATION; SAID WRAPPER BEING COATED ON THE EXTERIOR SURFACE ONLYWITH A WAX HAVING A MELTING POINT OF BETWEEN 150* AND 165*F. ANDCONTAINING THEREIN NOT MORE THAN 2% OF A FUNGISTATIC EDIBLE, FATSOLUBLE, STEAM-DISTILLABLE, ORGANIC CARBOXYLIC ACID HAVING UNSATURATIONADJACENT OT THE CARBOXYL GROUP AND THAT PORTION OF THE MOLECULECONTAINING THE UNSATURATION IS A MEMBER SELECTED FROM THE CLASSCONSISTING OF ALIPHATIC AND AROMATIC HYDROCARBON GROUPS AND GROUPSCONTAINING AN ADDITIONAL UNSATURATED LINKAGE MAKING UP A CONJUGATEDDOUBLE BOND SYSTEM WITH THE UNSATURA-TION ADJACENT TO THE CARBOXYLGROUP.